19678638535 has 4 divisors (see below), whose sum is σ = 23614366248. Its totient is φ = 15742910824.

The previous prime is 19678638527. The next prime is 19678638557. The reversal of 19678638535 is 53583687691.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 19678638535 - 2³ = 19678638527 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1967863849 + ... + 1967863858.

It is an arithmetic number, because the mean of its divisors is an integer number (5903591562).

Almost surely, 2^19678638535 is an apocalyptic number.

19678638535 is a deficient number, since it is larger than the sum of its proper divisors (3935727713).

19678638535 is an equidigital number, since it uses as much as digits as its factorization.

19678638535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3935727712.

The product of its digits is 32659200, while the sum is 61.

The spelling of 19678638535 in words is "nineteen billion, six hundred seventy-eight million, six hundred thirty-eight thousand, five hundred thirty-five".